Block backpack



FIG. 1 is a right front perspective view of a block backpack showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The block backpack is characterized by an arrangement of various sizes and shapes of protruding blocks which are spaced from one another and are arranged in fitting alignment.

The structural features depicted by broken lines have been shown to illustrate portions of the block backpack that form no part of the claimed design. 

CLAIM We claim the ornamental design for a block backpack, substantially as shown and described. 